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 ###Instrução: Quantos países têm um PIB (nominal) de $29,9 bilhões?
 ###Tabelas: CREATE TABLE western_bay_of_plenty_district (western_bay_of_plenty_district_id AUTO_INCREMENT PRIMARY KEY, Name VARCHAR, Years VARCHAR, Gender VARCHAR, Area VARCHAR, Authority VARCHAR, Decile INT, Roll INT) CREATE TABLE winners_of_the_colonial_turf_cup (winners_of_the_colonial_turf_cup_id AUTO_INCREMENT PRIMARY KEY, Year INT, Winner VARCHAR, Jockey VARCHAR, Trainer VARCHAR, Owner VARCHAR, Distance (Miles) VARCHAR, Time VARCHAR) CREATE TABLE top_20_countries_by_tally (top_20_countries_by_tally_id AUTO_INCREMENT PRIMARY KEY, Rank INT, Country/Territory VARCHAR, Miss World INT, 1st Runner-up INT, 2nd Runner-up INT, 3rd Runner-up INT, 4th Runner-up INT, 5th Runner-up INT, 6th Runner-up INT, Semifinalists INT, Total INT) CREATE TABLE prospective_members (prospective_members_id AUTO_INCREMENT PRIMARY KEY, Country VARCHAR, Population INT, Area (km²) INT, GDP (nominal) VARCHAR, GDP per capita (nominal) VARCHAR) CREATE TABLE internal_representation (internal_representation_id AUTO_INCREMENT PRIMARY KEY, Type VARCHAR, Sign INT, Exponent INT, Significand INT, Total bits INT, Exponent bias INT, Bits precision INT, Number of decimal digits VARCHAR)  
SELECT COUNT GDP per capita (nominal) FROM prospective_members WHERE GDP (nominal) = $29.9 billion